When you want to escape the heat of Vegas and you find yourself around Mandalay Bay, Excalibur, and Luxor, the tram is a good way to do so.
There are two trams, one that is non stop from the Excalibur to Mandalay Bay and the other that stops at Luxor. The tram is air conditioned, clean, and fairly quick. If you don't feel like walking through the three connected hotels, the tram is your option.